DETAILED SCENARIO
Introduction
Scenarios for category V events can vary greatly depending on the specific national situation and the proximity of extra-territorial nuclear power plants. Hence, it is not possible to provide a generic scenario that is suitable for all countries.
Generally, a scenario for a category V type exercise is quite simple. The complexity of the exercise and the challenges introduced are primarily based on the national assessment response, and on the peripheral events that are introduced in the exercise to make it more realistic.
The following is one of the many examples of a typical category V exercise. It is followed by a section of potential challenges that could be part of the exercise. The challenges introduced will depend on the objectives of the exercise. It is those challenges that will make a category V exercise useful.
Narrative
At 06:00 h, an emergency occurs at the Nuckie Power Plant in country Y, 100 km away from the country X border. The Nuckie power plant is a 1000 MWe PWR. A release through a leaking outlet damper starts at 10:00 h. It is estimated that 20% of the core has melted. Sprays are inoperative. The release rate from the containment is 10% per hour.
Country X is notified by country Y at 07:00 h, and by the IAEA at 09:00 h.
The wind is blowing toward country X at 13 m/s.
Country X depends heavily on country Y for the import of meat, cereal and wine. There are several farms located around the Nuckie power plant.
Event sequences:
Time Event
06:00 LOCA with loss of emergency core injection at the Nuckie power plant.
07:00 Notification from country Y received by country X.
09:00 Notification from the IAEA received by country Y.
10:00 First media report of the emergency.
11:00 Country X is informed by country Y that a release has started and is expected to go on for hours.
13:00 Radiation detected at the border with country Y.
14:00 Country X is informed by country Y that an evacuation of 8 km around the station is under way.
15:00 Country Y requests assistance from country X for the survey of the 100 × 20 km area extending between the plant and the border with country X.
Time Event
16:00 Country Y informs country X that the release has decreased and is expected to be under control within 2 hours.
18:00 Country Y informs country X that the release has stopped.
19:00 Winds shift.
20:00 Radiation readings at the border with country Y start decreasing.
Potential challenges
The following considerations can be introduced in the category V scenario to make the exercise more realistic and to allow the achievement of exercise objectives:
• Key members of the organization are missing and must be replaced by their alternates.
• Requests for information by members of the public regarding the safety of country X residents who are in country Y.
• A large volume of requests from the media.
• The media report incorrect facts, e.g. that people in country Y who live near the country X border are preparing for an evacuation.
• Requests for full briefings by ministers.
• Meat and wine merchants report that they will stop importing products from country Y.
• Border forces refuse to let people from country Y come into country X.
• Airport workers refuse to service airplanes from country Y.
• All flights to country Y cancelled by the airlines.
• Anti-nuclear groups call for a stop of all nuclear research and use of radiation in country X.
• Unconfirmed reports of a secondary explosion at the Nuckie power plant.
• Telephone main switchboards crash under the large number of calls to emergency services.
• Roadblocks around the affected power plant in the neighbouring country have stopped all major traffic of goods into country X.
GENERAL SCENARIOS
General scenario 1: Incineration of a 60Co source in a smelter
A source of several TBq of 60Co mixed in with scrap metal is burned in a smelter in country X. The plant does not have a gate monitor capable of preventing the ingress of radioactive sources. Monitoring stations downwind of the plant promptly detect an increase in ambient radiation levels, but do not immediately recognise the source. The wind is blowing towards neighbouring country Y. Country X notifies country Y.
This scenario is an interesting alternate to a nuclear power plant emergency in the far field. It also leads to low-level trans-boundary impacts, and requires both countries to cooperate to estimate the level of risk and the protective actions, if any, that may have to be adopted. Until the nature of the airborne contamination and the source of the release are known, authorities will have to make decisions on the basis of very few data.
Scenario 2: Emergency involving a nuclear powered vessel
A nuclear powered vessel moving outside territorial waters of country X is the scene of a reactor emergency that leads to a short release of radioactive material to the atmosphere. The vessel surfaces and is waiting for assistance from the country of origin. The winds are blowing toward country X.
This scenario presents challenges and a degree of complexity that are different from those encountered when dealing with land-based reactors. There may not be bilateral agreement between the country of origin and country X. There are no fixed monitoring stations over the water. It may be difficult to obtain detailed information on the events from the ship. This forces the national authorities of country X to make decisions based on very little information and to focus their attention on the monitoring data. It may also test their ability to develop an appropriate monitoring strategy (e.g. aerial surveys) to make the best use of the information available.
Possible additional challenges
Adding individual events that are not necessarily essential for the conduct of the exercise but that potentially increase realism can enhance the value of the exercise. The following are examples of exercise challenges.
• Have participants decide which special non-government groups need to be considered, and what their specific concerns and needs are.
• Have the players identify and correct/monitor unsubstantiated information that has made its way into the public domain.
• Have media sources introduce conflicting information and observe how players attempt to prevent public confusion.
• Have players deal with the potential impact of differing environmental and food monitoring standards on public perception and trust.
APPENDIX IX: EXAMPLES OF SCENARIOS FOR RESPONSE EXERCISES TO